A hydraulic vibration-damping support of that type is disclosed, for example, in Document FR-A-2 751 042, in which the rigid second piece of the rigid partition is a casting.
That known vibration-damping support is quite satisfactory as regards technical operation. In particular, it is known that the resonance frequency of the constricted passage, which resonance frequency is also the frequency at which the vibration-damping support offers its best performance for large-amplitude vibration, depends on the ratio between the length and the equivalent diameter of the constricted passage: by implementing the constricted passage in two stages, it is thus possible to obtain a passage length that is long and thus a resonance frequency that is low for said constricted passage, which can be necessary in certain uses.
Unfortunately, the above-mentioned vibration-damping support suffers from the drawback that the casting of its rigid partition is relatively costly to make, and also relatively weighty, which tends to increase both the cost and the weight of the vibration-damping support.